There are a few items displayed from the past - paintings, photos, statues, maps, stamps, clothes, fans, furniture, and more.
The few opinions of the museum are divided. Many see this as an interesting museum for the history of Madrid, and some see it as a waste of time. Either way, since the entrance is free, you won't lose any money if you go in for a look.
Our recommendations: the museum is for history fans only, others might be bored here.